Why HEIC Exists and Why It Is Awkward
HEIC is Apple's name for images stored in the HEIF container, encoded with HEVC. Its advantage is straightforward: for the same perceived quality it produces files roughly half the size of JPEG, which is why iPhones have defaulted to it since iOS 11. It also supports features JPEG cannot, including 16-bit colour depth, transparency, image sequences such as Live Photos, and depth maps used for portrait effects.
The awkwardness is licensing. HEVC is covered by a complicated patent pool, which has made broad adoption slow outside Apple's ecosystem. The practical result is a format that is excellent on the device that created it and unpredictable everywhere else: older Windows installations need a codec extension, many web applications reject the file outright, printing services frequently cannot accept it, and older Android devices may not display it at all.
JPG or WebP: Which to Convert To
| JPG | WebP |
|---|
| Compatibility | Universal, works everywhere | All modern browsers; some older desktop software still struggles |
| File size | Larger | Roughly 25–35% smaller at similar quality |
| Transparency | Not supported | Supported |
| Best for | Printing, sharing, uploading to forms and older systems | Websites and storage where size matters |
The short version: choose JPG when the file is going to someone else or into a system you do not control, and WebP when it is going onto a website you run or into storage where the space saving is worth having.
What Is Lost in Conversion
Being clear about this matters more than the conversion itself. HEIC to JPG is a lossy-to-lossy transcode, so the image is decoded and re-encoded rather than simply repackaged. At a high quality setting the visible difference is negligible on ordinary photographs, but it is not mathematically identical and repeated round trips will accumulate degradation. Convert from the original each time rather than converting a conversion.
Several HEIC-specific features cannot survive the move to JPEG at all. Transparency is discarded, since JPEG has no alpha channel. Depth maps used for portrait mode blur are lost, which means the blur is baked in as it appeared rather than remaining adjustable. Live Photos reduce to their single key frame, with the motion discarded. Colour depth beyond 8 bits per channel is reduced, which is only noticeable in very smooth gradients such as skies. And wide-gamut Display P3 colour is typically converted to sRGB, which can make highly saturated colours look slightly flatter.
Keep the HEIC originals until you are certain the converted copies are what you need. Conversion is one-way in practice, and the discarded depth and motion data cannot be recovered from a JPEG.
What About EXIF Data
Photographs carry embedded metadata: the camera model, exposure settings, orientation, the date and time, and often precise GPS coordinates. Two aspects of this matter during conversion.
Orientation is the practical one. Phones record the physical rotation as a metadata flag rather than rotating the pixels, so a conversion that ignores the flag produces sideways images. This tool applies the orientation during conversion so the output appears the right way up everywhere.
Location is the privacy one. If you are about to publish photographs publicly, be aware that GPS coordinates in EXIF can reveal a home address with considerable precision. Most social platforms strip metadata on upload, but files sent by email, messaging apps in document mode, or uploaded to a personal website often retain it. Checking before publishing is a good habit.
Stopping the Problem at Source
If HEIC files are a recurring nuisance rather than a one-off, an iPhone can simply stop producing them. Under Settings, Camera, Formats, choosing "Most Compatible" instead of "High Efficiency" makes the camera capture JPEG directly. You lose the storage saving and the advanced features, but every file works everywhere without a conversion step.
There is also a separate transfer setting. Under Settings, Photos, at the bottom of the screen, "Transfer to Mac or PC" can be set to "Automatic", which converts images to a compatible format when copying them off the device, or "Keep Originals", which does not. If your photos arrive as HEIC when you plug the phone in, this is usually the setting responsible.
Batch Conversion and Practical Limits
Converting a whole camera roll at once is the normal case, and the constraint is memory rather than any imposed quota. Each image is decoded to raw pixels before re-encoding, and a 12-megapixel photograph occupies far more memory decoded than it does on disk. Desktop browsers handle large batches comfortably; phones are more constrained, and very large batches on mobile can stall.
If a batch fails partway, process in smaller groups, close other tabs to free memory, and keep the tab in the foreground, since browsers throttle background tabs. Occasional individual files fail because they use an HEIC variant your browser's decoder does not implement, most often image sequences or unusual bit depths, in which case opening and re-exporting the file on the device that created it usually resolves it.
Your Photos Are Never Uploaded
Camera rolls are the most personal file collection most people have, and they routinely contain photographs of children, homes, documents and identity papers along with embedded GPS coordinates. Handing a folder of those to an unknown web service to save a conversion step is a poor exchange, and it is exactly what most online HEIC converters ask for.
This one does not. Your files are read from disk by your browser using the File API, decoded and re-encoded in memory on your own machine, and written back as downloads. There is no upload, no server-side processing, no temporary copy on anyone else's disk and no retention period. Nothing is limited, watermarked or counted, because there is no service on the other end to meter. Load the page, switch off your internet connection entirely, and convert a batch successfully; that is the simplest demonstration that nothing is being transmitted.
More questions about HEIC files
Why can't Windows open my HEIC files?
HEIC uses HEVC encoding, which is covered by a patent pool, so support is not installed by default on many systems. Recent Windows versions may prompt for a codec extension from the Microsoft Store, while older installations cannot open the files at all. Converting to JPG avoids the issue entirely.
Should I convert HEIC to JPG or WebP?
JPG when the file is going to someone else, to a printing service, or into any system you do not control, because it works everywhere. WebP when the image is for a website you run or for storage, since it is roughly 25 to 35 per cent smaller at similar quality and supports transparency.
Does converting HEIC to JPG lose quality?
Slightly. It is a decode and re-encode rather than a repackage, so at high quality settings the difference is negligible on ordinary photographs but not mathematically identical. Always convert from the original rather than converting an earlier conversion, as degradation accumulates.
What happens to Live Photos and portrait mode blur?
Live Photos reduce to their single key frame and the motion is discarded. The depth map used for portrait blur is lost, so the blur is baked in exactly as it appeared and can no longer be adjusted. Transparency is also discarded, since JPEG has no alpha channel.
How do I stop my iPhone creating HEIC files?
In Settings, Camera, Formats, choose Most Compatible instead of High Efficiency and the camera will capture JPEG directly. Separately, Settings, Photos, Transfer to Mac or PC set to Automatic will convert images when copying them off the device.